JP2002108064A - Electrostatic charging member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charging member minimizing the noise regardless of an electrostatic charging member. SOLUTION: This electrostatic charging member has a layer structure incorporating at least a conductive elastic layer as a core material. The impact resilience rate of the above conductive elastic body layers is equal to or below 75, or the impact resilience rate of the layer structure as a whole is equal to or below 75.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a charging member used in an electrophotographic apparatus such as a copying machine, a laser printer, a facsimile, and a composite OA machine.

[0002]

2. Description of the Related Art An image forming apparatus using an electrophotographic system forms a uniform charge on an image carrier (photoreceptor), and forms an electrostatic latent image by a laser or the like that modulates an image signal. The electrostatic latent image is developed with the charged toner to form a toner image. Then, the desired transfer image can be obtained by electrostatically transferring the toner image to the recording medium via an intermediate transfer member or directly.

As described above, in an image forming apparatus using an electrophotographic system, a charging process for forming a uniform charge on an image carrier is performed. As one of charging members for performing such a charging process, there is a contact type charging system. Such a charging member of the contact charging type generally has an advantage that a current to be applied is small and an amount of generated ozone is very small, but has a problem that noise is large.

[0004]

It is considered that this noise has a correlation with the hardness of the charging member, and in the past, noise was generally suppressed by lowering the hardness. However, in order to lower the hardness of the charging member, that is, to make it softer, it is necessary to add an additive such as a plasticizer, oil, etc., to cause problems such as freeze, bloom, and to suppress these. There is also a problem that the layer structure needs to be complicated. Further, when the hardness of the charging member is reduced, a problem of abrasion resistance may occur. As described above, at present, measures against the noise of the charging member are still insufficient.

An object of the present invention is to solve the above conventional problems and achieve the following objects. That is, an object of the present invention is to provide a charging member with low noise regardless of the hardness of the charging member.

[0006]

The above object is achieved by the following means. That is, the present invention provides: <1> a charging member having a layer structure including at least a conductive elastic layer on a core material, wherein the conductive elastic layer has a rebound resilience of 75 or less. It is. <2> A charging member comprising a core material having a layer structure including at least a conductive elastic layer, and a rebound resilience of the entire layer structure is 75 or less. <3> The charging member according to claim 1 or 2, wherein the hardness of the entire layer structure is 45 to 90 degrees. <4> The charging member according to any one of claims 1 to 3, wherein the elastic layer mainly includes epichlorohydrin rubber. <5> A second rubber component is further added to the elastic layer from 1 to 5
The charging member according to claim 4, wherein the charging member is contained by weight%. <6> The charging member according to claim 5, wherein the second rubber component is at least one selected from acrylic rubber and nitrile butadiene rubber.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The charging member of the present invention is
It has a layer structure including at least a conductive elastic layer, and the conductive elastic layer has a rebound resilience of 75 or less. The resilience of the entire layer structure is 75 or less. Hereinafter, in the present invention, the rebound resilience of the elastic layer is simply referred to as “rebound resilience”, and the resilience of the entire layer structure is referred to as “roll resilience”.
That. Since the charging member of the present invention has a specific rebound resilience, noise is small regardless of the hardness of the charging member.

The charging member of the present invention has a rebound resilience of 75 or less, preferably 70 or less, and more preferably 65 or less. When the rebound resilience exceeds 75, noise increases. Here, the rebound resilience is the rebound resilience of a conductive elastic layer described later. A test piece having the same composition as the elastic layer constituting the charging member is prepared, and is referred to as “Resilience Tester (KK). (Manufactured by Toyo Seiki Seisakusho)) and measured according to “JISK 6255”. When the charging member is composed of a plurality of elastic layers, each is measured individually.

In the charging member of the present invention, the roll rebound elastic modulus is 75 or less, preferably 70 or less,
More preferably, it is 65 or less. If the roll resilience exceeds 75, noise increases. Here, the roll rebound resilience is a rebound resilience in a state in which all layers (including a surface layer and other layers in addition to a conductive elastic layer) constituting a charging member are laminated on a core material. Specifically, a charging member (charging roll) was prepared, and was set on a resilience tester (manufactured by Toyo Seiki Seisakusho), which was modified so that it could be supported and fixed, and then set to "JIS K 6255".
(Use a charging member (charging roll) instead of the test piece)
Is a value measured according to In the resilience tester (manufactured by Toyo Seiki Seisaku-sho, Ltd.), the trajectory of the hammer hitting part coincides with the charging roll center (center in the length direction of the roll axis) instead of the holder member for setting the test piece. A support member for supporting and fixing both ends of the charging roll (shaft) as described above. The charging roll is supported and fixed so that it is hit when the center of gravity of the hammer reaches the lowest point. The roll rebound elastic modulus is measured by hitting the charging roll center with a hammer.

In the charging member of the present invention, the hardness of the entire layer structure is preferably 45 to 90 degrees, more preferably 6 to 90 degrees.
0 to 85 degrees, and more preferably 65 to 80 degrees. This hardness is a hardness that has conventionally been considered to be high in noise. However, in the present invention, since it has the above-described specific rebound resilience, even with high hardness, there is little noise. Here, the hardness is the hardness of all the layers constituting the charging member (including the surface layer and other layers in addition to the conductive elastic body layer),
Specifically, in a state where all the constituent layers are laminated on the core material,
This is a value measured by the Asker C method.

In the charging member of the present invention, the layer structure is not particularly limited as long as it includes a conductive elastic layer and has the above specific resilience. And a layer structure in which a viscoelastic layer and a surface layer are sequentially laminated. The layer structure includes a conductive elastic body layer and a surface layer, an intermediate layer provided between the conductive elastic body layer and the surface layer, and an adhesive layer provided between the core material and the conductive elastic body layer. Another layer such as a layer may be provided. Each of these layers may be composed of a single layer or a plurality of layers. In the present invention, the above specific rebound resilience and hardness can be satisfied by appropriately selecting various materials and thicknesses constituting these layers. The details will be described below.

<Core material> In the present invention, the core material is
Conventionally known metals such as iron, nickel-plated iron, copper, and stainless steel can be used. As the shape of the core material,
In general, it is generally a shaft shape used as a core material of a charging member.

<Electroconductive Elastic Layer> In the present invention, the electroconductive elastic layer is made of an elastic substance having conductivity, and
It satisfies the above-mentioned regulation of the rebound resilience. The material and composition are not particularly limited as long as such a material is used, but usually, a conductive material is dispersed and blended in a base material serving as a base. Examples of the conductive substance include an organic ion conductive substance, carbon black, and a metal oxide. In the present invention, as the conductive substance used for the conductive elastic layer, an organic ion conductive substance is particularly preferable from the viewpoint of resistance uniformity in the constituent layer of the charging member.

As the organic ion conductive substance, a quaternary ammonium salt (eg, lauryl trimethyl ammonium,
Perchlorates such as stearyltrimethylammonium, octadodecyltrimethylammonium, dodecyltrimethylammonium, hexadecyltrimethylammonium, denatured fatty acid and dimethylethylammonium, chlorate, borofluoride, sulfate, ethosulfate, halogen Benzyl salts (benzyl bromide salts, benzyl chloride salts, etc.), aliphatic sulfonates, higher alcohol sulfates, higher alcohol ethylene oxide addition sulfates, higher alcohol phosphates,
Higher alcohol ethylene oxide addition phosphoric acid ester salts, various betaines, higher alcohol ethylene oxide, polyethylene glycol fatty acid esters, polyhydric alcohol fatty acid esters, and the like.

As the organic ion conductive substance, polyhydric alcohols (1,4 butanediol, ethylene glycol,
Complexes of polyethylene glycol, propylene glycol, polyethylene glycol and the like and derivatives thereof with metal salts, and complexes of monools (such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether) with metal salts are also included. Examples of the metal salt include Li
ClO ₄ , LiCF ₃ SO ₃ , LiAsF ₆ , LiBF ₄ ,
NaClO ₄ , NaSCN, KSCN, NaCl, etc., Group 1 metal salts of the periodic table; electrolytes, such as NH ⁴⁺ salts;
(ClO ₄ ) ₂ , Ba (ClO ₄ ) ₂ etc., a metal salt of Group 2 of the periodic table; active hydrogen which reacts with isocyanate such as at least one or more hydroxyl group, carboxyl group, primary or secondary amine group Having a group having the formula: Specifically, as such a complex, PEL (L
complex of iClO ₄ and polyethylene glycol).

Of these, a quaternary ammonium salt is preferred as the organic ion conductive substance from the viewpoint of compatibility with the substrate. This quaternary ammonium salt has a weight average molecular weight (Mw) of 10 from the viewpoint of preventing bleeding.
Those having 0 to 600 are preferable, and those having 150 to 300 are more preferable. As the quaternary ammonium salt, those having one or more benzene rings are particularly preferable from the viewpoint of preventing bleeding.

Preferred organic ion conductive materials include quaternary ammonium salts represented by the following general formula (I).

[0018]

Embedded image

In the above formula, R ¹ , R ² and R ³ are each independently hydrogen or a hydrocarbon group which may contain a substituent, preferably hydrogen, an alkyl group having 1 to 20 carbon atoms, 6 to 10 aryl groups or 7 to 2 carbon atoms
0 is an alkylaryl group. T represents a linking group containing a single bond, preferably a single bond or a group having 1 carbon atom.
To 5 alkylene groups.

Hereinafter, specific examples of suitable quaternary ammonium salts will be shown, but the present invention is not limited thereto.

[0021]

Embedded image

Examples of the metal oxide used as the conductive substance include zinc oxide, titanium oxide, tin oxide, and antimony-doped tin oxide.

Carbon black can be used as the conductive substance. Particularly, when acidic carbon black is used, an excessive current flows in a part of the carbon black, which is less susceptible to oxidation due to repeated voltage application. Due to the effect of oxygen-containing functional groups attached to
The resistance variation can be reduced, the electric field dependency is also reduced, and electric field concentration due to energization is less likely to occur. As a result, resistance change due to energization is prevented, uniformity of electric resistance is improved, electric field dependence is small, and resistance change due to environment is small, and uniform charging is possible. For this reason, it is possible to prevent electric field concentration caused by large aggregates of carbon black and leakage discharge such as pinhole leak, which is considered to be caused by dielectric breakdown, and also prevent toner from sticking. Further, image quality defects caused by uneven charging and leak discharge due to resistance change and resistance variation, and fluctuations in image density due to environmental fluctuations are reduced, and high-quality images can be obtained over a long period of time. Also,
Carbon black eliminates the need to perform coupling treatment for improving dispersibility, addition of insulating particles, metal oxides, and the like, and simplifies the manufacturing process. Further, since carbon black is electronically conductive, there is no problem of bleeding using ionic conductivity, for example, an ionic conductive material that contains an ether segment and tends to contaminate the image carrier. Accordingly, there is no need to provide a layer or the like for preventing bleeding, and the manufacturing process is similarly simplified.

Acidic carbon blacks include:
Oxygen-containing functional groups (such as carboxylic acid groups, hydroxyl groups (for example, phenolic hydroxyl groups), lactone groups, quinoid groups, etc.) are very abundant on the surface. In general, the oxygen-containing functional groups on the carbon black surface are only carbon To give a polarity to the carbon black, which improves the affinity with the base material (binder polymer) and enables uniform dispersion, which is widely recognized in systems containing solvents such as inks and paints. However, it is presumed that this is also true when dry kneading and dispersion are performed.

The carbon black can be produced by a contact method. Examples of the contact method include a channel method and a gas black method. Carbon black can also be produced by a furnace black method using gas or oil as a raw material. If necessary, after these treatments, a liquid phase oxidation treatment with nitric acid or the like may be performed. Note that carbon black can be produced by a contact method, but this contact method is hardly produced at present due to problems such as air pollution, and is usually produced by a closed furnace method. In the furnace method, only carbon black having a high pH and a low volatile content is usually produced, but the pH can be adjusted by subjecting the carbon black to the above-mentioned liquid acid treatment. For this reason, carbon black obtained by furnace method production and adjusted to have a pH of 6 or less by post-process treatment is also considered to be included in the present invention.

As the carbon black, specifically, "Color Black FW200" manufactured by Degussa (pH 2.
5, FW2 (pH 2.5, volatile matter 16.5%), FW2V (pH 2.5, volatile matter 16.5%), "Special Black 6" (pH 2.
5, volatile matter 18%), same as "5" (pH 3, volatile matter 15
%), "4" (pH 3, volatile matter 14%), "4A"
(PH 3, volatile content 14%)), "Printex 150
T "(pH 4, 10% volatiles) [these can be produced by a gas black process similar to the channel process but are classified in the industry as channel black]; Cabot's" REGAL 400R "(pH 4. 0, volatile content 3.5
%), The same "MONARCH 1000" (pH 2.5,
Volatile content 9.5%), same as “MONARCH 1300”
(PH 2.5, volatile content 9.5%), same as "Mogul L"
(PH 2.5, volatile content 4.5%); "30" manufactured by Mitsubishi Chemical Corporation
30B "(pH 6.5, volatile matter 0.5%);

The conductive substance may be used alone in the base material, but may be used in combination of two or more kinds. The electric resistance (surface resistivity, volume resistivity) of the elastic layer may be used. In addition, it can be blended so as to meet the requirements of the whole system such as mechanical strength, hardness, rebound resilience and the like. The amount of the conductive substance added to the substrate may be appropriately adjusted so as to satisfy the requirements of the entire system.
It is generally preferred that the amount be about 5 to 50 parts by weight based on 00 parts by weight.

The base material of the conductive elastic layer is not particularly limited, and conventionally known materials can be used. For example, polyimide, polyester, polyether ether ketone, polyamide, polycarbonate, polyvinylidene fluoride (PVDF) ), Resin materials such as polyfluoroethylene-ethylene copolymer (ETFE) and epoxy (EP); polyurethane, chlorinated polyisoprene, nitrile butadiene rubber (NBR), chloroprene rubber, ethylene propylene rubber (EPM), hydrogenated polybutadiene And elastic materials such as butyl rubber, silicone rubber, acrylic rubber, and epichlorohydrin rubber.
Thermoplastic elastomers, heat-shrinkable (thermosetting) rubbers, foamable rubbers, and non-diene-based rubbers irrespective of the diene type as described above can also be suitably used. These can also be used as an alloy (blend material) in which two or more kinds are blended.

The base material of the conductive elastic layer is mainly composed of epichlorohydrin rubber among the above-mentioned materials in view of the electrical characteristics (uniformity of resistance, stability, etc.) of the rubber itself. preferable. In addition, the phrase “mainly composed of epichlorohydrin rubber” means that the main component of the base material component is epichlorohydrin rubber, and the component occupying 50% by weight or more of the base material component is “mainly composed”. Included in the concept of

The base material of the conductive elastic layer preferably contains epichlorohydrin rubber as a main component and further contains 1 to 5% by weight of a second rubber component. By containing the second rubber component, the processability can be improved while maintaining the electrical characteristics. If the second rubber component is less than 1% by weight, the effect of containing the second rubber component will not be obtained, and if the second rubber component exceeds 5% by weight, the electrical properties of the main component will be impaired. There is a fear. Examples of the second rubber component include any of the rubber materials described above as the material of the base material, and in particular, at least one selected from acrylic rubber, nitrile butadiene rubber (NBR), and urethane rubber Is preferred in that it does not affect the electrical characteristics of the main component.

In the conductive elastic layer, a curing agent, a plasticizer, a vulcanization accelerator and the like may be used, if necessary, in addition to the base material and the conductive material. In the case of foaming, a foaming agent or the like can be appropriately used. The thickness of the conductive elastic layer is not particularly limited, but is preferably about 1 to 10 mm, and more preferably about 2 to 5 mm.

The conductive elastic material layer is formed by dissolving the base material, the conductive material, and other substances added as necessary in a suitable solvent and applying the resulting solution to a core material. Can be formed by kneading a compound with a base material and forming a compound, winding the material around a core material and pressing, or by a known molding method such as injection molding. In the case of forming by applying, it is desirable to apply the layers repeatedly to secure a predetermined thickness.

<Surface Layer> In the present invention, the surface layer is a layer which functions to adjust resistance, block bleeding from the conductive elastic layer, and protect from contaminants.
A conductive material is dispersed in a base material serving as a base. Examples of the conductive substance include an organic ion conductive substance, carbon black, and a metal oxide.

As the conductive substance, those similar to those described in the section of the conductive elastic layer can be used. In particular, the use of carbon black in the surface layer prevents bleeding. Preferred from a viewpoint.

The above-mentioned conductive substance may be used alone in the base material, but any two or more kinds may be used.
In addition to the electrical resistance (surface resistivity, volume resistivity) as the surface layer, it can be blended so as to meet the requirements of the entire system such as mechanical strength, hardness, rebound resilience, and the like. The amount of the conductive substance added to the substrate may be appropriately adjusted so as to satisfy the requirements of the entire system.
For a quaternary ammonium salt, 0.0
About 1 to 5 parts by weight, or 20 for carbon black
It is generally preferred to be about 200 parts by weight.

As the base material of the surface layer, the same materials as those described in the section of the conductive elastic layer can be used. In the surface layer, the aliphatic polyester resin is subjected to a crosslinking reaction with the melamine resin. It is desirable to use a thermosetting resin which does not adversely affect the mechanical strength and the rebound resilience of the elastic layer.

The mixing ratio of the melamine resin to the aliphatic polyester resin is 100 to 100 parts by weight.
It is preferably 0 parts by weight, more preferably 45 to 55 parts by weight. If the amount of the melamine resin is less than 30 parts by weight, the crosslinking may be weakened and the strength may not be obtained.
If it exceeds 0 parts by weight, the hardness may increase and the flexibility may deteriorate, which is not preferred.

When the thermosetting resin is used as the base material of the surface layer, the surface layer may further contain a fluorine-based polymer compound and / or a silicone-based polymer compound. It is desirable in preventing. It is desirable that the fluorine-based polymer compound and / or the silicone-based polymer compound be contained as fine particles having a particle diameter of 15 μm or less in view of durability and surface characteristics. The particle diameter of such fine particles is more preferably in the range of 0.1 to 5.

The content of the fluorine-based polymer compound and / or the silicone-based polymer compound is preferably within a range of 5 to 200 parts by weight based on 100 parts by weight of the thermosetting resin. More preferably, it is within the range of 75 parts by weight. If these contents are less than 5 parts by weight, the effect of containing them cannot be obtained and 2
If the amount is more than 00 parts by weight, problems such as a rough surface and poor workability may occur.

The surface layer is formed by dissolving the above-mentioned base material, the above-mentioned conductive substance, and other substances added as necessary in a suitable solvent, and applying the resultant solution to the core material to form the base material. It can be formed by winding the compound kneaded and compounded with a core material and pressing it, or by a known molding method such as injection molding. In the case of forming by applying, it is desirable to apply the layers repeatedly to secure a predetermined thickness. When a thermosetting resin is used as the base material, it is preferable to heat at a temperature sufficient for curing after coating or molding.

<Application of the Present Invention> The charging member of the present invention described above is used for a copying machine, a laser printer, a facsimile,
It is suitably used as a charging member in a contact-type charging system charger in an electrophotographic apparatus such as a composite OA apparatus.

An electrophotographic apparatus to which the charging member of the present invention is suitably applied will be described in detail with reference to the drawings. FIG.
FIG. 1 is a schematic cross-sectional view illustrating an example of an electrophotographic apparatus to which the charging member of the present invention is applied. The electrophotographic apparatus shown in FIG.
An electrophotographic photoreceptor 10; a charger 11 comprising the charging member of the present invention for charging the surface of the electrophotographic photoreceptor 10; a power supply 12 for applying a voltage to the charger 11; An image input device 13 for forming a latent image on the surface of the electrophotographic photoreceptor 10 with a toner, and a developing device 14 for developing a latent image formed on the surface of the electrophotographic photosensitive member 10 to obtain a toner image. , A cleaner 16 for removing residual toner and the like on the surface of the electrophotographic photoreceptor 10, a static eliminator 17 for removing residual potential on the surface of the electrophotographic photoreceptor 10, and a transfer to the surface of the transfer-receiving body 20 And a fixing device 18 for fixing the formed toner image by heat and / or pressure.

The charger 11 comprising the charging member of the present invention
It operates by the voltage supplied from the power supply 12, and charges the surface of the photoconductor. In addition, an image input device 13, a developing device 14, a transfer device 15, a cleaning device 16, a static eliminator 17, and a fixing device 1
The configuration 8 is not particularly limited in the present invention, and any configuration conventionally known in the field of electrophotography can be applied as it is. Note that the static eliminator 17 is not necessarily provided.

The operation of the electrophotographic apparatus shown in FIG. 1 will be described. The surface of the electrophotographic photosensitive member 10 is uniformly charged by the charger 11, and then a latent image is formed by the image input device 13. The latent image formed on the surface of the electrophotographic photoreceptor 10 is developed by a toner built in the developing device 14 to form a toner image. The toner image formed on the surface of the electrophotographic photoreceptor 10 is transferred to the surface of the transfer receiving member 20 inserted between the electrophotographic photoreceptor 10 and the transfer unit 15 facing the electrophotographic photoreceptor 10. And / or fixed by pressure or the like. On the other hand, the transferred electrophotographic photoreceptor 10
The residual toner on the surface is removed by the cleaning device 16. Then, before proceeding to the next image forming cycle, the residual potential on the surface of the electrophotographic photosensitive member 10 is removed by the neutralizer 17.

[0045]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. (Examples 1 to 5) <Preparation of charging member> A core material (Ni electroless treated SUM) having a length of 331 mm and 8 mmφ was prepared, and an adhesive layer (5 μm) made of a phenol-based conductive adhesive was provided on the core material. According to Tables 1 and 2, a conductive elastic layer (3 mm) and a surface layer (20 μm) were sequentially laminated to prepare charging rolls (charging members) of Examples 1 to 5. In the table, "ph
"r" indicates the number of parts by weight based on 100 parts by weight of the base material.

[0046]

[Table 1]

[0047]

[Table 2]

<Evaluation> The obtained charging rolls were evaluated as follows. Table 3 shows the results.

—Resilience—The rebound resilience was determined by preparing a test piece having the same composition as the conductive elastic layer of each charging roll as described above, and using it as a “resilience tester (manufactured by Toyo Seiki Seisakusho Co., Ltd.) And measured according to "JIS K 6255".

-Roll rebound elastic modulus- The roll rebound elastic modulus is determined by charging each charging roll as described above.
“Resilience Tester (Toyo Seiki Co., Ltd.)”
It was set in a modified machine and measured according to "JIS K 6255" (using a charging member (charging roll) instead of a test piece).

-Hardness- The hardness was measured for each charging roll by the Asker C method as described above.

-Noise- The noise was measured by using a charge roll made by Fuji Xerox Co., Ltd.
r Laser Wind 3300 ”(photoreceptor diameter φ8
4 mm), the sound level meter (integrated precision sound level meter “NL-
14 "manufactured by Rion Co., Ltd.). Fig. 2
As shown in FIG.
The tip (sound collecting unit 52a) of the sound level meter 52 was installed at a position 10 cm radially away from the surface on the downstream side in the rotation direction (arrow in the figure) 90 degrees, and the noise was measured. The measurement is
The measurement was performed three times under the following measurement conditions, and the measured value is an average value of the max values under each measurement condition.
Each measurement condition is shown below.

Measurement conditions; laboratory zone (temperature 22 ° C.,
Humidity 55% RH), process speed 104mm / s,
Current value (V _h [690 V], I _AC [1.1 mA, 500
Hz]) Measurement conditions: Lab zone (temperature 22 ° C., humidity 55% R
H), process speed 250 mm / s, current value (V _h
[650V], I _AC [2.6mA, 1820Hz])

[0054]

[Table 3]

From Table 3, it can be seen that the charging roll of the example has a low rebound resilience despite having a high hardness.
It can be seen that the noise is low.

[0056]

As described above, according to the present invention, it is an object of the present invention to provide a charging member having low noise regardless of the hardness of the charging member.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of an electrophotographic apparatus to which a charging member of the present invention is applied.

FIG. 2 is a diagram illustrating a method for measuring noise in an embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Electrophotographic photoreceptor 11 Charging device 12 Power supply 13 Image input device 14 Developing device 15 Transfer device (transfer member) 16 Cleaning device 17 Static eliminator 18 Fixing device 20 Transfer object

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 33:08) C08L 33:08) (C08L 71/03 (C08L 71/03 9:02) 9:02 (C08L 71/03 (C08L 71/03 75:04) 75:04) (72) Inventor Hideo Nishinomiya 1900 Itunacho, Suzuka-shi, Mie Prefecture Inside Suzuka Fuji Xerox Co., Ltd. (72) Inventor Takeshi Ueyama Mie 1900, Ifuna-cho, Suzuka Suzuka Fuji Xerox Co., Ltd. Xerox Co., Ltd. (72) Inventor Masato Ono 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Fuji Xerox Co., Ltd. (72) Inventor Minoru Rokutan Minamiashi, Kanagawa Prefecture 1600 Ichitakematsu, Fuji Xerox Co., Ltd. (72) Inventor Tetsuya Kawatani 1600 Takematsu, Minamiashigara, Kanagawa Prefecture F Xerox Co., Ltd. F-term (reference) 2H003 AA11 BB11 CC05 3J103 AA02 BA41 FA04 GA02 GA52 GA57 GA58 GA60 HA03 HA12 HA20 HA53 4J002 AC072 BG042 CH041 CK022 DA036 DD036 DE196 EC046 ED026 EN136 EV236 FD116 GQ02

Claims (6)

[Claims] 1. A layer structure including at least a conductive elastic layer on a core material, wherein the conductive elastic layer has a rebound resilience of 7
The charging member, wherein the number is 5 or less. 2. A charging member, wherein a core material has a layer structure including at least a conductive elastic layer, and the resilience of the entire layer structure is 75 or less. 3. The charging member according to claim 1, wherein the hardness of the entire layer structure is 45 to 90 degrees. 4. The charging member according to claim 1, wherein the elastic layer mainly comprises epichlorohydrin rubber. 5. The charging member according to claim 4, wherein the elastic layer further contains 1 to 5% by weight of a second rubber component. 6. The second rubber component is at least one selected from acrylic rubber, nitrile butadiene rubber (NBR), and urethane rubber.
3. The charging member according to 1.